Coolant Operating Temps at Idle
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Joined: Feb 2022
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Coolant Operating Temps at Idle
So I started the car this morning and let it idle while I was dusting / cleaning for a morning drive, (weather is perfect). When I got back in the car the temp gauge was about half way between the last mark and the 260 mark...Yikes whats wrong? So I revved it up a few time and temp started going down. Checked the fans and both were running but not what I would call high speed. I took off and as I drove the temp came back to the halfway mark. I took it out on a not very well used freeway and got it up to around 100 for a mile or two and the temp settled at the halfway mark, I guess all good. It appears to me its an air issue across the radiator. If it sits it gets hot, going down the road it's normal.
Questions for the experts, is this normal for the temp to rise at idle? Do the fans have different speeds or just one? I tried to find the operating temp in the manual but no luck. I have looked at the radiator and it looks clean but I think I'll hose it down today just to be sure.
As always thanks for your help with a rookie first time Vette owner.
Bill
Questions for the experts, is this normal for the temp to rise at idle? Do the fans have different speeds or just one? I tried to find the operating temp in the manual but no luck. I have looked at the radiator and it looks clean but I think I'll hose it down today just to be sure.
As always thanks for your help with a rookie first time Vette owner.
Bill
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Sounds normal to me. You can't keep a C4 cool at idle very long, it'll run right up to thermostat temp, and with no airflow will continue after a bit to fan ON temps.
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Thanks, appreciate the quick response. So far just minor issues to fix. Engine, trans and rear end all seem to be performing well or at least like they should. I just put a set of Nittos on it and at 103 the other day hands off the wheel and she ran straight and solid so it appears the suspension is good as well.
Bill
Bill
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From: New Jersey
Being from your description it sounds like you have a later C4 with analog gauges.... maybe it wouldn't hurt to get the digital readout as well to confirm the gauge itself is reading correctly? Then at least you know if it was actually overheating or just the gauge.
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From: South Florida
You need a real gauge. I do not recommend electrical senders In general.
Use a quality mechanical guage IMO
Ideal idle/cruise Engine Coolant temperature is 209-218*F (around the boiling point of water) Some newer vehicles run even warmer
Thermostat should not open until at least 180-195*F most cars (thermostat helps the engine warm up quickly to reduce wear)
Pay attention to whether you are measuring the water leaving the radiator (Entering the engine) Or water that is leaving the engine and entering the radiator. Generally do not measure water entering the engine due to thermostating as it may not read correctly and fails to report engine temp rise rate.
Couple tips
-Cold coolant or oil will increase engine wear (let an engine warm up without load)
-Higher temps improve engine efficiency (economy)
addl reading
https://www.corvetteforum.com/forums...post1604546854
https://www.corvetteforum.com/forums...post1604570294
Use a quality mechanical guage IMO
Ideal idle/cruise Engine Coolant temperature is 209-218*F (around the boiling point of water) Some newer vehicles run even warmer
Thermostat should not open until at least 180-195*F most cars (thermostat helps the engine warm up quickly to reduce wear)
Pay attention to whether you are measuring the water leaving the radiator (Entering the engine) Or water that is leaving the engine and entering the radiator. Generally do not measure water entering the engine due to thermostating as it may not read correctly and fails to report engine temp rise rate.
Couple tips
-Cold coolant or oil will increase engine wear (let an engine warm up without load)
-Higher temps improve engine efficiency (economy)
addl reading
https://www.corvetteforum.com/forums...post1604546854
https://www.corvetteforum.com/forums...post1604570294
